The National Mining Association (NMA) and the Nuclear Energy Institute (NEI) filed suit in Arizona challenging the 20-year ban on uranium mining on about 1 million acres of public land near the Grand Canyon.

The ban was put in place by Interior Secretary Ken Salazar earlier this year.

In documents filed with the U.S. District Court, the NMA and NEI challenged the constitutionality of the mining ban as well as the validity of the environmental studies used to justify it. They asked a judge to reopen the land.

Salazar imposed the ban citing evidence that extracting uranium so near to the canyon could endanger ground water or seep into the Colorado River. He said the 20-year time-out would allow a more thorough scientific review of the possible threats.

The Mining Association and the Energy Institute cited past Supreme Court decisions in arguments that Salazar’s action was illegal and said the environmental studies did not support the ban.

Hal Quinn, president and chief executive officer of the mining group, said the Interior Department “offered no evidence … that a million-acre land grab is necessary to avoid environmental harm” and argued that the agency did not adequately analyze the economic effects of its action or consider other alternatives to the ban.

Richard Myers, an Energy Institute vice president, said the ban is “designed to protect against situations and circumstances that no longer exist. It is a mistake to judge today’s uranium-mining activities by practices and standards from 50 to 60 years ago.”

The suit asks the court to overturn the ban and declare the section of the Federal Land Policy and Management Act cited by Salazar as unconstitutional. In a third request that would affect future decisions, the groups also want the court to rule that the Interior secretary does not have the authority to block mining on blocks of more than 5,000 acres, or about 8 sq miles, of public lands.

A coalition of environmental groups immediately announced plans to intervene in the lawsuit on behalf of the federal government. The Sierra Club, the Center for Biological Diversity and the Grand Canyon Trust will be represented by Earthjustice and the Western Mining Action Project.